These terms are used without explanation in API documentation. And I think they are being used consistently... However, they are Drupal-specific or have specific meanings in Drupal that are not generally known to software developers.

This makes it difficult for experienced programmers who are new to Drupal to understand what is going on by reading class/function API documentation.

Proposed resolution

a) Make a list of these terms, with definitions.
b) Put it in a Topic/@defgroup, probably in system.api.php

This way at least we could point programmers new to Drupal to this page so that they could learn about this terminology.

Remaining tasks

a) Make the list of possibly unfamiliar terms. This should exclude terms that are used on php.net or that are standard Computer Science terms, unless they have a Drupal-specific meaning that is different from their standard meaning.
b) Write definitions for these terms.
c) Create a @defgroup topic containing the terms and definitions. They should be listed alphabetically using our standard list formatting, like:

Concerning Resolutions
a) It looks like most Drupalism terms are listed at https://drupal.org/glossary thankfully reducing the amount of discovery needed for this, and should narrow our focus to terms introduced by D8.

b) I support this but worry about the maintenance cost in term addition and editing vs the already existing glossary page.

Yes, that is a good point. Maybe we just need to make sure the new D8 terms are added to the glossary, and this issue can be about collecting the new terms and making sure they are there? Like "provider" for instance, and "container"?

Really a "provider" in the plugin discovery systems is an internal structure and the fact that it shows up at all to users(through the definition) is a leak that probably shouldn't happen because the entire point of plugins is to interact with the class directly. I'll try to follow up with that.

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